A power semiconductor module, having built-in switching elements and diode elements connected in anti-parallel with the switching elements, is widely employed in devices, such as power converters that perform DC-AC and DC-DC conversions. Silicon (Si) semiconductors are conventionally used for switching elements and diode elements; however, in recent times, product development is underway to use wide bandgap semiconductors, typified by silicon carbide (SiC) semiconductors. As compared to the Si semiconductors, the SiC semiconductors have features such as being low-loss and operable at high temperatures and having high dielectric withstand voltage. Using the SiC semiconductors allows reduction in size and loss of a power semiconductor module, and further allows reduction in size of a radiator that is attached to the power semiconductor module and increase in efficiency of a power converter that uses the power semiconductor module.
Using the SiC semiconductors for both switching elements and diode elements increases the above advantageous effects; however, because the switching elements have complex structures as compared to the diode elements, the use of the SiC semiconductors for the switching elements leads to the creation of a fabrication problem. For this reason, a semiconductor module has been proposed in which Si semiconductors are used for switching elements, while SiC semiconductors are used for diode elements alone, and the Si switching elements and the SiC diode elements are placed above one and the same baseplate (refer to Patent Document 1, for example).